friends wedding

a friend that lives out of state asked me to be in her wedding in October. I haven't heard from her since April. I don't have any info about the wedding, dress, etc. I contacted her recently with no reply. my question is, do I give up or do I try again? I don't want to be annoying but I'm a teacher and need to figure out days off in advance. also a cousin is getting married in October and I already got their invitation!!